Reaction kinetics of the Shvo-catalyzed dehydrogenation of 1-phenyl-1,3-propanediol-derived lignin model compound

Abstract

<p>The Shvo-catalyst allows to perform hydrogen transfer from the benzylic hydroxyl group of 1-phenyl-1,3-propanediol to 2-butanone. This paper describes kinetic studies on the Shvo-catalyzed dehydrogenation of 1-phenyl-1,3-propanediol as a lignin model compound. The influence of catalyst amount, temperature and the presence of 2-butanol were investigated. It was found that the apparent rate constant of the reaction depends on the catalyst concentration, with the rate expression having 0.5 order in the same. From the study of reaction rates at different temperatures, the apparent activation energy E_a of 1-phenyl-1,3-propanediol conversion was found to be 77 kJ/mol. In the presence of a twenty-fold excess of 2-butanone, the dehydrogenation reaction can be considered as pseudo first order in terms of the substrates. Based on the obtained experimental data, a kinetic model of the dehydrogenation of 1-phenyl-1,3-propanediol, describing the catalyst concentration dependence, temperature influence and the concentrations of 2-butanone and 2-butanol, was developed.<br></p>